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[Ntp] Antw: [EXT] Microbursts of NTP packets

Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de> Tue, 18 August 2020 07:31 UTC

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Date: Tue, 18 Aug 2020 09:31:43 +0200
From: Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de>
To: watsonbladd@gmail.com, "ntp@ietf.org" <ntp@ietf.org>
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Subject: [Ntp] Antw: [EXT] Microbursts of NTP packets
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>>> Watson Ladd <watsonbladd@gmail.com> schrieb am 18.08.2020 um 03:20 in Nachricht
<CACsn0cm7PX-NzJBrA6RR_u=1c3PWjga8t+iccd3Am_VFsDWoKQ@mail.gmail.com>:
> Dear NTP WG,
> 
> We're observing short bursts of high numbers of NTP queries at one
> point of presence, exceeding the queue length of the listening ntp
> socket, and leading to drops. The bursts are very short, so the
> overall qps is nothing special. I'm quite mystified as to what the
> possible causes could be.

I think an important questions is: From the same source or not?
Also: Time queries, or control mode packets? If so it might be an attempt to attack...

> 
> This is unfortunately leading to packet drops. If any operators have
> seen this, their input on possible causes and solutions is welcome.
> 
> Sincerely,
> Watson Ladd
> 
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